Combined combustion chamber and skimmer blower for portable asphalt plant



Nov. 22, 1960 w. WRIGHT 2,961,227

COMBINED COMBUSTION CHAMBER AND SKIMMER BLOWER FOR PORTABLE ASPHALT PLANT Filed Sept. 18, 1958 United States Patent COlVlBlNED COMBUSTION CHAMBER AND SKIM- MER BLOWER FOR PORTABLE ASPHALT PLANT Wilbur Wright, 3800 Wood St., Lansing, Mich.

Filed Sept. 18, 1958, Ser. No. 761,872

3 Claims. (Cl. 26321) This invention relates to machinery for making asphalt, and has particular reference to a combined combustion chamber and skimmer blower, for use with a portable asphalt plant, such as disclosed in my co-pending application, Serial No. 761,871, filed September 18, 1958, of which this application may be considered a continuation in part.

An object of this invention is to generally improve asphalt making devices, and to provide a combustion chamber for a portable asphalt plant, which is applied with cooling air from a skimmer blower, which is located in the tower section of the plant, which air is then circulated through the drier section and dust collectors of the plant.

Another object of the invention is to provide means for cooling the outer walls of the combustion chamber, with air from the skimmer blower, whereby to prevent the overheating of the combustion chamber, and to obtain a more uniform control over the drying operation.

Another object of the invention is to provide a device of the character described, which is simple in construction, economical to manufacture, and efiicient in operation.

The foregoing and other objects and advantages of the invention will become more apparent, as the description proceeds, reference being made to the accompanying drawing, forming part of the within disclosure, in which drawing:

Fig. 1 is a schematic view, with parts in section, of a device embodying the invention.

Fig. 2 is a fragmentary left end elevation of the device shown in Fig. 1.

Referring now more particularly to the drawing, it will be understood that in the embodiment herein disclosed, the reference character 7 indicates, in general, the combustion chamber of the drier section 7A of a portable asphalt plant, such as disclosed in my co-pending application, referred to above. The combustion chamber 7 is supplied with oil, or other suitable fuel, from a source (not shown), through a fuel line 8, which is controlled by a suitable valve 9. The air for the combustion process is supplied by a blower 10, and an air line 11. The fuel and air are thoroughly mixed in the member 12, and the mixture is burned in the combustion chamber 7, which has a central opening 13A. The combustion chamber is in the form of a Venturi tube in reverse, which siphons in additional air through the opening 13A, which air, together with the products of combusion, are blown into the drier section 7A, of the portable asphalt plant, as is more particularly described in my said co-pending application. The housing 14 is provided with a flange 14A, which may be used as a means for welding or otherwise securing the combustion chamber 7 to the drier section 7A of the asphalt plant.

In order to cool the outer walls of the combustion chamber 7, I provide a peripheral housing 14. The outer wall of the housing 14 is corrugated, as shown in Fig. 2,

so that there is a greatly increased surface area to be contacted by the air, as is more fully described hereinafter. Air from the pipe 16 enters the space 15, defined by the wall of the tube 13, of the combustion chamber, and the wall 14, of the peripheral housing. The pipe 16 receives air from the skimmer blower 17, which is located in the tower section 18 of the portable asphalt plant. The skimmer blower skims dust laden air from the top of the sizing screens 19, and elevator shaft 20, which comprise parts of the tower section 18 of the device,

which is more fully described in my co-pending' application.

Air which is skimmed from the tower section 18 of the asphalt plant, passes through the blower 17, the pipe 16, and is circulated around the combustion chamber 7, through space 15. This air helps greatly to carry off the heat and cool the walls of the combustion chamber 7. Additional heat is radiated from the combustion chamber 7 through the corrugated walls of the housing 14. The dust laden air is discharged from the space 15, into and through the drier 7A and the dust collectors (not shown).

The functioning of the apparatus just described, accomplishes the following results: First, that of removing most of the dust from the tower section of the asphalt plant; second, it helps to cool the Walls of the combustion chamber, to prevent the combustion chamber from buming out unreasonably; third, it increases the volume of air passing through the drier section of the plant; and lastly, helps to maintain a uniformity in the drying of the aggregates, as they pass through the drier. This greatly assists in maintaining a uniform end product of the plant, and tends to increase the overall capacity of the plant, by shortening the cycles of operation.

It is believed the operation of the device is obvious from the foregoing description.

Having described my invention, what I claim and desire to secure by Letters Patent is:

1. In combination with an asphalt plant having a drier section and a tower section in which is mounted an elevator shaft and sizing screens, the combination of a heat generating device, secured to and in communication with the interior of said drier section, said device consisting of a tubular member having a flared intake end, fuel and air supply means for said tubular member, a housing around said tubular member defining a secondary air space between said tube and said housing, and an air blower in said tower section in communication with the said secondary air space and the interior of said drier section for cooling said tubular member and forcing dust laden air from over said sizing screens into said drier section.

2. The structure of claim 1 in which said housing is corrugated to provide a greater surface to be contacted by the air from said blower and the outer portions of said corrugated housing are flared.

3. The structure of claim 1 in which said housing is corrugated to provide a greater surface to be contacted by the air from said blower and the outer portions of said housing are flared, there being a flange on said flared portions for securing said device to said drier section.

References Cited in the file of this patent UNITED STATES PATENTS 1,603,760 Furkert Oct. 19, 1926 1,801,431 Irish Apr. 21, 1931 2,421,902 Neuschotz June 10, 1947 2,501,962 Pierce Mar. 28, 1950 2,689,457 Kruppe Sept. 21, 1954 2,788,959 Sherwin Apr. 16, 1957 

